The Johnson City driver set the fast time in qualifying, 14.940 seconds, and pulled away from Piney Flats racer Hayden Woods in the early going around the three-eighths-mile concrete oval.
Chuckey’s Nik Williams passed Woods for second on lap 17, but the No. 1 Ford was too strong out front and Shell captured his third win of the season.
Williams finished second, followed by Woods, Robbie Ferguson of Jonesborough and defending track champion Kres VanDyke of Abingdon. Trey Bayne, Joey Trent, Derek Lane, Dillon Hodge and Kyle Barnes completed the top 10.
Per NASCAR Whelen All-American Series rules, the top eight finishers were inverted for the second 35-lap race. Lane and Trent led the field to the green ahead of VanDyke, Bayne and Woods.
The late-race battle saw Williams' No. 32 Chevrolet riding the rear bumper of VanDyke's No. 15 Chevy lap after lap. As the two raced down the front straightaway to take the white flag, Williams used the bump-and-run move to take leader VanDyke up the banking.
The duo raced off turn 2 down the backstretch, side by side into the third turn. Williams, on the bottom, used a strong run off the fourth turn to narrowly edge VanDyke for his sixth Late Model Stock Car victory of the season.
Shell, Woods and Ferguson crossed the line behind them, followed by Bayne, Trent, Barnes, Hodge and Wayne Hale.
Shell ended the night with an 11-point lead over VanDyke in the track championship standings. The final race is scheduled for this Friday, Aug. 31.
Chase Dixon of Abingdon earned his third feature win in the first twin 20-lap event by outrunning Kirby Gobble, Royce Peters, rookie Alex Miller and Daniel McMurray. Gobble, also from Abingdon, visited victory lane in the second race by winning over Dixon, Peters, Miller and Rusty Clendenin.
Kingsport drivers Keith Helton and John Ketron maintained their longstanding rivalry in Pure 4, trading the lead back and forth before Helton captured his seven win of the season. Billy Byington finished second ahead of Brandon Southerland, Kenny Absher and Ketron.
Kevin Canter of Abingdon continued to rule the Mod 4 division, cruising to his 11th feature win of the season. His celebration was muted, however, after Canter's 74-year-old grandfather, Hershell Robinette, violently slammed the inside concrete retaining wall following contact from another car exiting the second corner on lap 17, which ended the race prematurely because of the time limit.
Robinette was transported to a local hospital by ambulance for precautionary measures and eventually released.
Rob Austin of Castlewood recorded his third straight Pure Street win by outrunning Joey Sykes, Sammy Ferguson, Kevin Darnell and veteran Jon Cook of Jonesborough.